The road to tailored adjuvant chemotherapy for all four non-pancreatic periampullary cancers: An international multimethod cohort study.

BACKGROUND: Despite differences in tumour behaviour and characteristics between duodenal adenocarcinoma (DAC), the intestinal (AmpIT) and pancreatobiliary (AmpPB) subtype of ampullary adenocarcinoma and distal cholangiocarcinoma (dCCA), the effect of adjuvant chemotherapy (ACT) on these cancers, as well as the optimal ACT regimen, has not been comprehensively assessed. This study aims to assess the influence of tailored ACT on DAC, dCCA, AmpIT, and AmpPB. PATIENTS AND METHODS: Patients after pancreatoduodenectomy for non-pancreatic periampullary adenocarcinoma were identified and collected from 36 tertiary centres between 2010 - 2021. Per non-pancreatic periampullary tumour type, the effect of adjuvant chemotherapy and the main relevant regimens of adjuvant chemotherapy were compared. The primary outcome was overall survival (OS). RESULTS: The study included a total of 2866 patients with DAC (n = 330), AmpIT (n = 765), AmpPB (n = 819), and dCCA (n = 952). Among them, 1329 received ACT, and 1537 did not. ACT was associated with significant improvement in OS for AmpPB (P = 0.004) and dCCA (P < 0.001). Moreover, for patients with dCCA, capecitabine mono ACT provided the greatest OS benefit compared to gemcitabine (P = 0.004) and gemcitabine - cisplatin (P = 0.001). For patients with AmpPB, no superior ACT regime was found (P > 0.226). ACT was not associated with improved OS for DAC and AmpIT (P = 0.113 and P = 0.445, respectively). DISCUSSION: Patients with resected AmpPB and dCCA appear to benefit from ACT. While the optimal ACT for AmpPB remains undetermined, it appears that dCCA shows the most favourable response to capecitabine monotherapy. Tailored adjuvant treatments are essential for enhancing prognosis across all four non-pancreatic periampullary adenocarcinomas.

Distinguishing Clinical From Statistical Significances in Contemporary Comparative Effectiveness Research.

OBJECTIVE: To determine the prevalence of clinical significance reporting in contemporary comparative effectiveness research (CER). BACKGROUND: In CER, a statistically significant difference between study groups may or may not be clinically significant. Misinterpreting statistically significant results could lead to inappropriate recommendations that increase health care costs and treatment toxicity. METHODS: CER studies from 2022 issues of the Annals of Surgery , Journal of the American Medical Association , Journal of Clinical Oncology , Journal of Surgical Research , and Journal of the American College of Surgeons were systematically reviewed by 2 different investigators. The primary outcome of interest was whether the authors specified what they considered to be a clinically significant difference in the "Methods." RESULTS: Of 307 reviewed studies, 162 were clinical trials and 145 were observational studies. Authors specified what they considered to be a clinically significant difference in 26 studies (8.5%). Clinical significance was defined using clinically validated standards in 25 studies and subjectively in 1 study. Seven studies (2.3%) recommended a change in clinical decision-making, all with primary outcomes achieving statistical significance. Five (71.4%) of these studies did not have clinical significance defined in their methods. In randomized controlled trials with statistically significant results, sample size was inversely correlated with effect size ( r = -0.30, P = 0.038). CONCLUSIONS: In contemporary CER, most authors do not specify what they consider to be a clinically significant difference in study outcome. Most studies recommending a change in clinical decision-making did so based on statistical significance alone, and clinical significance was usually defined with clinically validated standards.

Outcome of Minimally Invasive and Open Pancreatoduodenectomy in Patients with Intestinal- and Pancreatobiliary Subtype Ampullary Cancer: An International Multicenter Cohort Study.

OBJECTIVE: To compare minimally invasive and open pancreatoduodenectomy in different subtypes of ampullary adenocarcinoma. SUMMARY BACKGROUND DATA: Ampullary adenocarcinoma (AAC) is widely seen as the best indication for minimally invasive pancreatoduodenectomy (MIPD) due to the lack of vascular involvement and dilated bile and pancreatic duct. However, it is unknown whether outcomes of MIPD for AAC differ between the pancreatobiliary (AAC-PB) and intestinal (AAC-IT) subtypes as large studies are lacking. METHODS: This is an international cohort study, encompassing 27 centers from 12 countries. Outcome of MIPD and open pancreatoduodenectomy (OPD) were compared in patients with AAC-IT and AAC-PB. Primary end points were R1 rate, lymph node yield, and 5-year overall survival (5yOS). RESULTS: Overall, 1187 patients after MIPD for AAC were included, of whom 572 with AAC-IT (62 MIPD, 510 OPD) and 615 with AAC-PB (41 MIPD and 574 OPD). The rate of R1 resection was not significantly different between MIPD and OPD for both AAC-IT (3.4% vs 6.9%, P=0,425) and AAC-PB (9.8% vs 14.9%, P=0,625). AAC-IT, more lymph nodes were resected with MIPD group (19 vs 16, P=0.007), compared to OPD. The 5y-OS did not differ after MIPD and OPD for both AAC-IT (56.8% vs 59.5%, P=0.827 and AAC-PB (52.5% vs 44.4%, P=0.357). The rates of surgical complication between MIPD and OPD did not differ between AmpIT and AmpPB. DISCUSSION: This international multicenter study found no differences in outcomes between MIPD and OPD for AAC-IT and AAC-PB. MIPD and OPD demonstrated comparable outcomes in oncological resection, survival and surgical outcomes for both subtypes of AAC.

Predicting Long-term Disease-free Survival After Resection of Pancreatic Ductal Adenocarcinoma: A Nationwide Cohort Study.

OBJECTIVE: To develop a prediction model for long-term (≥5 years) disease-free survival (DFS) after the resection of pancreatic ductal adenocarcinoma (PDAC). BACKGROUND: Despite high recurrence rates, ~10% of patients have long-term DFS after PDAC resection. A model to predict long-term DFS may aid individualized prognostication and shared decision-making. METHODS: This nationwide cohort study included all consecutive patients who underwent PDAC resection in the Netherlands (2014-2016). The best-performing prognostic model was selected by Cox-proportional hazard analysis and Akaike's Information Criterion, presented by hazard ratios (HRs) with 95% confidence intervals (CIs). Internal validation was performed, and discrimination and calibration indices were assessed. RESULTS: In all, 836 patients with a median follow-up of 67 months (interquartile range 51-79) were analyzed. Long-term DFS was seen in 118 patients (14%). Factors predictive of long-term DFS were low preoperative carbohydrate antigen 19-9 (logarithmic; HR 1.21; 95% CI 1.10-1.32), no vascular resection (HR 1.33; 95% CI 1.12-1.58), T1 or T2 tumor stage (HR 1.52; 95% CI 1.14-2.04, and HR 1.17; 95% CI 0.98-1.39, respectively), well/moderate tumor differentiation (HR 1.44; 95% CI 1.22-1.68), absence of perineural and lymphovascular invasion (HR 1.42; 95% CI 1.11-1.81 and HR 1.14; 95% CI 0.96-1.36, respectively), N0 or N1 nodal status (HR 1.92; 95% CI 1.54-2.40, and HR 1.33; 95% CI 1.11-1.60, respectively), R0 resection margin status (HR 1.25; 95% CI 1.07-1.46), no major complications (HR 1.14; 95% CI 0.97-1.35) and adjuvant chemotherapy (HR 1.74; 95% CI 1.47-2.06). Moderate performance (concordance index 0.68) with adequate calibration (slope 0.99) was achieved. CONCLUSIONS: The developed prediction model, readily available at www.pancreascalculator.com, can be used to estimate the probability of long-term DFS after resection of pancreatic ductal adenocarcinoma.

Interobserver Variability in the International Study Group for Pancreas Surgery (ISGPS)-Defined Complications After Pancreatoduodenectomy: An International Cross-Sectional Multicenter Study.

OBJECTIVE: To determine the interobserver variability for complications of pancreatoduodenectomy as defined by the International Study Group for Pancreatic Surgery (ISGPS) and others. SUMMARY BACKGROUND DATA: Good interobserver variability for the definitions of surgical complications is of major importance in comparing surgical outcomes between and within centers. However, data on interobserver variability for pancreatoduodenectomy-specific complications are lacking. METHODS: International cross-sectional multicenter study including 52 raters from 13 high-volume pancreatic centers in 8 countries on 3 continents. Per center, 4 experienced raters scored 30 randomly selected patients after pancreatoduodenectomy. In addition, all raters scored six standardized case vignettes. This variability and the 'within centers' variability were calculated for twofold scoring (no complication/grade A vs grade B/C) and threefold scoring (no complication/grade A vs grade B vs grade C) of postoperative pancreatic fistula (POPF), post-pancreatoduodenectomy hemorrhage (PPH), chyle leak (CL), bile leak (BL), and delayed gastric emptying (DGE). Interobserver variability is presented with Gwet's AC-1 measure for agreement. RESULTS: Overall, 390 patients after pancreatoduodenectomy were included. The overall agreement rate for the standardized cases vignettes for twofold scoring was 68% (95%-CI: 55%-81%, AC1 score: moderate agreement) and for threefold scoring 55% (49%-62%, AC1 score: fair agreement). The mean 'within centers' agreement for twofold scoring was 84% (80%-87%, AC1 score; substantial agreement). CONCLUSION: The interobserver variability for the ISGPS defined complications of pancreatoduodenectomy was too high even though the 'within centers' agreement was acceptable. Since these findings will decrease the quality and validity of clinical studies, ISGPS has started efforts aimed at reducing the interobserver variability.

Poor Prognostic Factors in Long-Term Survivors of Resected Pancreatic Ductal Adenocarcinoma: An International, Multicenter Cohort Study.

OBJECTIVE: To measure the rate of LTS in resected PDAC and determine the association between predictors of OS and LTS. SUMMARY BACKGROUND DATA: Long-term survival (>5 y, LTS) remains rare in pancreatic ductal adenocarcinoma (PDAC). Multiple predictors of overall survival (OS) are known but their association with LTS remains unclear. METHODS: An international, multicenter retrospective study was conducted. Included were patients from 2012-2019 with resected PDAC. Excluded were those with metastases at diagnosis or resection, R2 resections, and 90-day mortality. Predictors of OS were identified using multivariable Cox regression and their prevalence in patients with LTS assessed. LTS was calculated by excluding patients with shorter follow-up and predictors of LTS were identified using multivariable logistic regression. RESULTS: 3,003 patients were included (27.4% received neoadjuvant chemotherapy). Elevated baseline CA19-9, high tumor grade, nodal disease, and perineural and lymphovascular invasion were negative independent predictors of OS, while receipt of adjuvant chemotherapy predicted improved OS (all P<0.05). LTS was observed in 220/2,436 patients (9.0%), of whom 198 (90%) harbored poor prognostic factors: elevated baseline CA19-9 (58.1%), poor tumor differentiation (51.0%), nodal disease (46.8%), and perineural invasion (76.0%). Of those without any of these four features, 50.0% achieved LTS as compared to 21.3%, 13.3%, 5.2%, and 3.5% in those with 1, 2, 3, or 4 features. CONCLUSIONS: This bi-national cohort demonstrates a true LTS rate of 9.0% in resected PDAC. Clinicians should remain aware that presence of poor prognostic factors does not preclude LTS.

Classification of Intrahepatic Cholangiocarcinoma into Perihilar Versus Peripheral Subtype.

BACKGROUND: Intrahepatic cholangiocarcinoma (ICC) constitutes a group of heterogeneous malignancies within the liver. We sought to subtype ICC based on anatomical origin of tumors, as well as propose modifications of the current classification system. METHODS: Patients undergoing curative-intent resection for ICC, hilar cholangiocarcinoma (CCA), or hepatocellular carcinoma (HCC) were identified from three international multi-institutional consortia of databases. Clinicopathological characteristics and survival outcomes were assessed. RESULTS: Among 1264 patients with ICC, 1066 (84.3%) were classified as ICC-peripheral subtype, whereas 198 (15.7%) were categorized as ICC-perihilar subtype. Compared with ICC-peripheral subtype, ICC-perihilar subtype was more often associated with aggressive tumor characteristics, including a higher incidence of nodal metastasis, macro- and microvascular invasion, perineural invasion, as well as worse overall survival (OS) (median: ICC-perihilar 19.8 vs. ICC-peripheral 37.1 months; p < 0.001) and disease-free survival (DFS) (median: ICC-perihilar 12.8 vs. ICC-peripheral 15.2 months; p = 0.019). ICC-perihilar subtype and hilar CCA had comparable OS (19.8 vs. 21.4 months; p = 0.581) and DFS (12.8 vs. 16.8 months; p = 0.140). ICC-peripheral subtype tumors were associated with more advanced tumor features, as well as worse survival outcomes versus HCC (OS, median: ICC-peripheral 37.1 vs. HCC 74.3 months; p < 0.001; DFS, median: ICC-peripheral 15.2 vs. HCC 45.5 months; p < 0.001). CONCLUSIONS: ICC should be classified as ICC-perihilar and ICC-peripheral subtype based on distinct clinicopathological features and survival outcomes. ICC-perihilar subtype behaved more like carcinoma of the bile duct (i.e., hilar CCA), whereas ICC-peripheral subtype had features and a prognosis more akin to a primary liver malignancy.

Recurrent Intrahepatic Cholangiocarcinoma: A 10-Point Score to Predict Post-Recurrence Survival and Guide Treatment of Recurrence.

INTRODUCTION: Although up to 50-70% of patients with intrahepatic cholangiocarcinoma (ICC) recur following resection, data to predict post-recurrence survival (PRS) and guide treatment of recurrence are limited. METHODS: Patients who underwent resection of ICC between 2000 and 2020 were identified from an international, multi-institutional database. Data on primary disease as well as laboratory and radiologic data on recurrent disease were collected. Factors associated with PRS were examined and a novel scoring system to predict PRS (PRS score) was developed and internally validated. RESULTS: Among 986 individuals who underwent resection for ICC, 588 (59.6%) patients developed recurrence at a median follow up of 20.3 months. Among patients who experienced a recurrence, 97 (16.5%) underwent re-resection/ablation for recurrent ICC; 88 (15.0%) and 403 (68.5%) patients received intra-arterial treatment or systemic chemotherapy/supportive therapy, respectively. Patient American Society of Anesthesiologists (ASA) class > 2 (1 point), primary tumor N1/Nx status (1 point), primary R1 resection margin (1 point), primary tumor G3/G4 grade (1 point), carbohydrate antigen (CA) 19-9 > 37 UI/mL (2 points) at recurrence and carcinoembryonic antigen (CEA) > 5 ng/mL (2 points) at recurrence, as well as recurrent bilateral disease (1 point) and early recurrence (1 point) were included in the PRS score. The PRS score successfully stratified patients relative to PRS and demonstrated strong discriminatory ability (C-index 0.70, 95% confidence interval 0.68-0.72). While a PRS score of 0-3 was associated with a 3-year PRS of 62.5% following resection/ablation for recurrent ICC, a PRS score > 3 was associated with a low 3-year PRS of 35.5% (p = 0.03). CONCLUSIONS: The PRS score demonstrated strong discriminatory ability to predict PRS among patients who had developed recurrence following initial resection of ICC. The PRS score may be a useful tool to guide treatment among patients with recurrent ICC.

Benchmarks in Liver Resection for Intrahepatic Cholangiocarcinoma.

INTRODUCTION: Benchmarking in surgery has been proposed as a means to compare results across institutions to establish best practices. We sought to define benchmark values for hepatectomy for intrahepatic cholangiocarcinoma (ICC) across an international population. METHODS: Patients who underwent liver resection for ICC between 1990 and 2020 were identified from an international database, including 14 Eastern and Western institutions. Patients operated on at high-volume centers who had no preoperative jaundice, ASA class <3, body mass index <35 km/m2, without need for bile duct or vascular resection were chosen as the benchmark group. RESULTS: Among 1193 patients who underwent curative-intent hepatectomy for ICC, 600 (50.3%) were included in the benchmark group. Among benchmark patients, median age was 58.0 years (interquartile range [IQR] 49.0-67.0), only 28 (4.7%) patients received neoadjuvant therapy, and most patients had a minor resection (n = 499, 83.2%). Benchmark values included ≥3 lymph nodes retrieved when lymphadenectomy was performed, blood loss ≤600 mL, perioperative blood transfusion rate ≤42.9%, and operative time ≤339 min. The postoperative benchmark values included TOO achievement ≥59.3%, positive resection margin ≤27.5%, 30-day readmission ≤3.6%, Clavien-Dindo III or more complications ≤14.3%, and 90-day mortality ≤4.8%, as well as hospital stay ≤14 days. CONCLUSIONS: Benchmark cutoffs targeting short-term perioperative outcomes can help to facilitate comparisons across hospitals performing liver resection for ICC, assess inter-institutional variation, and identify the highest-performing centers to improve surgical and oncologic outcomes.

Early Onset Intrahepatic Cholangiocarcinoma: Clinical Characteristics, Oncological Outcomes, and Genomic/Transcriptomic Features.

INTRODUCTION: Data on clinical characteristics and disease-specific prognosis among patients with early onset intrahepatic cholangiocarcinoma (ICC) are currently limited. METHODS: Patients undergoing hepatectomy for ICC between 2000 and 2020 were identified by using a multi-institutional database. The association of early (≤50 years) versus typical onset (>50 years) ICC with recurrence-free (RFS) and disease-specific survival (DSS) was assessed in the multi-institutional database and validated in an external cohort. The genomic and transcriptomic profiles of early versus late onset ICC were analyzed by using the Total Cancer Genome Atlas (TCGA) and Memorial Sloan Kettering Cancer Center databases. RESULTS: Among 971 patients undergoing resection for ICC, 22.7% (n = 220) had early-onset ICC. Patients with early-onset ICC had worse 5-year RFS (24.1% vs. 29.7%, p < 0.05) and DSS (36.5% vs. 48.9%, p = 0.03) compared with patients with typical onset ICC despite having earlier T-stage tumors and lower rates of microvascular invasion. In the validation cohort, patients with early-onset ICC had worse 5-year RFS (7.4% vs. 20.5%, p = 0.002) compared with individuals with typical onset ICC. Using the TCGA cohort, 652 and 266 genes were found to be upregulated (including ATP8A2) and downregulated (including UTY and KDM5D) in early versus typical onset ICC, respectively. Genes frequently implicated as oncogenic drivers, including CDKN2A, IDH1, BRAF, and FGFR2 were infrequently mutated in the early-onset ICC patients. CONCLUSIONS: Early-onset ICC has distinct clinical and genomic/transcriptomic features. Morphologic and clinicopathologic characteristics were unable to fully explain differences in outcomes among early versus typical onset ICC patients. The current study offers a preliminary landscape of the molecular features of early-onset ICC.

Assessing quality of hepato-pancreato-biliary surgery: nationwide benchmarking.

BACKGROUND: Clinical auditing is a powerful tool to evaluate and improve healthcare. Deviations from the expected quality of care are identified by benchmarking the results of individual hospitals using national averages. This study aimed to evaluate the use of quality indicators for benchmarking hepato-pancreato-biliary (HPB) surgery and when outlier hospitals could be identified. METHODS: A population-based study used data from two nationwide Dutch HPB audits (DHBA and DPCA) from 2014 to 2021. Sample size calculations determined the threshold (in percentage points) to identify centres as statistical outliers, based on current volume requirements (annual minimum of 20 resections) on a two-year period (2020-2021), covering mortality rate, failure to rescue (FTR), major morbidity rate and textbook/ideal outcome (TO) for minor liver resection (LR), major LR, pancreaticoduodenectomy (PD) and distal pancreatectomy (DP). RESULTS: In total, 10 963 and 7365 patients who underwent liver and pancreatic resection respectively were included. Benchmark and corresponding range of mortality rates were 0.6% (0 -3.2%) and 3.3% (0-16.7%) for minor and major LR, and 2.7% (0-7.0%) and 0.6% (0-4.2%) for PD and DP respectively. FTR rates were 5.4% (0-33.3%), 14.2% (0-100%), 7.5% (1.6%-28.5%) and 3.1% (0-14.9%). For major morbidity rate, corresponding rates were 9.8% (0-20.5%), 28.1% (0-47.1%), 36% (15.8%-58.3%) and 22.3% (5.2%-46.1%). For TO, corresponding rates were 73.6% (61.3%-94.4%), 54.1% (35.3-100), 46.8% (25.3%-59.4%) and 63.3% (30.7%-84.6%). Mortality rate thresholds indicating a significant outlier were 8.6% and 15.4% for minor and major LR and 14.2% and 8.6% for PD and DP. For FTR, these thresholds were 17.9%, 31.6%, 22.9% and 15.0%. For major morbidity rate, these thresholds were 26.1%, 49.7%, 57.9% and 52.9% respectively. For TO, lower thresholds were 52.5%, 32.5%, 25.8% and 41.4% respectively. Higher hospital volumes decrease thresholds to detect outliers. CONCLUSION: Current event rates and minimum volume requirements per hospital are too low to detect any meaningful between hospital differences in mortality rate and FTR. Major morbidity rate and TO are better candidates to use for benchmarking.

Preoperative endoscopic biliary drainage by metal versus plastic stents for resectable perihilar cholangiocarcinoma.

BACKGROUND AND AIMS: Adequate preoperative biliary drainage (PBD) is recommended in most patients with resectable perihilar cholangiocarcinoma (pCCA). Most expert centers use endoscopic plastic stents rather than self-expandable metal stents (SEMSs). In the palliative setting, however, use of SEMSs has shown longer patency and superior survival. The aim of this retrospective study was to compare stent dysfunction of SEMSs versus plastic stents for PBD in resectable pCCA patients. METHODS: In this multicenter international retrospective cohort study, patients with potentially resectable pCCAs who underwent initial endoscopic PBD from 2010 to 2020 were included. Stent failure was a composite end point of cholangitis or reintervention due to adverse events or insufficient PBD. Other adverse events, surgical outcomes, and survival were recorded. Propensity score matching (PSM) was performed on several baseline characteristics. RESULTS: A total of 474 patients had successful stent placement, of whom 61 received SEMSs and 413 plastic stents. PSM (1:1) resulted in 2 groups of 59 patients each. Stent failure occurred significantly less in the SEMSs group (31% vs 64%; P < .001). Besides less cholangitis after SEMSs placement (15% vs 31%; P = .012), other PBD-related adverse events did not differ. The number of patients undergoing surgical resection was not significantly different (46% vs 49%; P = .71). Complete intraoperative SEMSs removal was successful and without adverse events in all patients. CONCLUSIONS: Stent failure was lower in patients with SEMSs as PBD compared with plastic stents in patients with resectable pCCA. Removal during surgery was quite feasible. Surgical outcomes were similar.

Impact of EUS in liver transplantation workup for patients with unresectable perihilar cholangiocarcinoma.

BACKGROUND AND AIMS: For a highly selected group of patients with unresectable perihilar cholangiocarcinoma (pCCA), liver transplantation (LT) is a treatment option. The Dutch screening protocol comprises nonregional lymph node (LN) assessment by EUS, and whenever LN metastases are identified, further LT screening is precluded. The aim of this study is to investigate the yield of EUS in patients with pCCA who are potentially eligible for LT. METHODS: In this retrospective, nationwide cohort study, all consecutive patients with suspected unresectable pCCA who underwent EUS in the screening protocol for LT were included from 2011 to 2021. During EUS, sampling of a "suspicious" nonregional LN was performed based on the endoscopist's discretion. The primary outcome was the added value of EUS, defined as the number of patients who were precluded from further screening because of malignant LNs. RESULTS: A total of 75 patients were included in whom 84 EUS procedures were performed, with EUS-guided tissue acquisition confirming malignancy in LNs in 3 of 75 (4%) patients. In the 43 who underwent surgical staging according to the protocol, nonregional LNs with malignancy were identified in 6 (14%) patients. Positive regional LNs were found in 7 patients in post-LT-resected specimens. CONCLUSIONS: Our current EUS screening for the detection of malignant LNs in patients with pCCA eligible for LT shows a limited but clinically important yield. EUS with systematic screening of all LN stations, both regional and nonregional, and the sampling of suspicious lymph nodes according to defined and set criteria could potentially increase this yield.

Long-term survivors after curative-intent resection for intrahepatic cholangiocarcinoma.

OBJECTIVES: The objective of the current study was to characterize prognostic factors related to long-term recurrence-free survival after curative-intent resection of intrahepatic cholangiocarcinoma (ICC). METHODS: Data on patients who underwent curative-intent resection for ICC between 2000 and 2020 were collected from an international multi-institutional database. Prognostic factors were investigated among patients who recurred within 5 years versus long-term survivors who survived more than 5 years with no recurrence. RESULTS: Among 635 patients who underwent curative-intent resection for ICC, 104 (16.4%) patients were long-term survivors with no recurrence beyond 5 years after surgery. Patients who survived for more than 5 years with no recurrence were more likely to have less aggressive tumor features, as well as have undergone an R0 resection versus patients who recurred within 5 years after resection. On multivariable analysis, tumor size (>5 cm) (HR: 1.535, 95% CI: 1.254-1.879), satellite lesions (HR: 1.253, 95% CI: 1.003-1.564), and lymph node metastasis (HR: 1.733, 95% CI: 1.349-2.227) were independently associated with recurrence within 5 years. Patients who recurred beyond 5 years (n = 23), 2-5 years (n = 60), and within 2 years (n = 471) had an incrementally worse post-recurrence survival (PRS, 28.0 vs. 20.0 vs. 12.0 months, p = 0.032). Among patients with N0 status, tumor size (>5 cm) (HR: 1.612, 95% CI: 1.087-2.390) and perineural invasion (PNI) (HR: 1.562,95% CI: 1.081-2.255) were risk factors associated with recurrence. Among patients with N1 disease, only a minority (5/128, 3.9%) of patients survived with no recurrence to 5 years. CONCLUSION: Roughly 1 in 6 patients survived for more than 5 years with no recurrence following curative-intent resection of ICC. Among N0 patients, tumor recurrence was associated with tumor size and PNI. Only a small subset of N1 patients experienced long-term survival.

Preoperative platelet count as an independent predictor of long-term outcomes among patients undergoing resection for intrahepatic cholangiocarcinoma.

BACKGROUND AND OBJECTIVES: An elevated platelet count may reflect neoplastic and inflammatory states, with cytokine-driven overproduction of platelets. The objective of this study was to evaluate the prognostic utility of high platelet count among patients undergoing curative-intent liver surgery for intrahepatic cholangiocarcinoma (ICC). METHODS: An international, multi-institutional cohort was used to identify patients undergoing curative-intent liver resection for ICC (2000-2020). A high platelet count was defined as platelets >300 *109/L. The relationship between preoperative platelet count, cancer-specific survival (CSS), and overall survival (OS) was examined. RESULTS: Among 825 patients undergoing curative-intent resection for ICC, 139 had a high platelet count, which correlated with multifocal disease, lymph nodes metastasis, poor to undifferentiated grade, and microvascular invasion. Patients with high platelet counts had worse 5-year (35.8% vs. 46.7%, p = 0.009) CSS and OS (24.8% vs. 39.8%, p < 0.001), relative to patients with a low platelet count. After controlling for relevant clinicopathologic factors, high platelet count remained an adverse independent predictor of CSS (HR = 1.46, 95% CI 1.02-2.09) and OS (HR = 1.59, 95% CI 1.14-2.22). CONCLUSIONS: High platelet count was associated with worse tumor characteristics and poor long-term CSS and OS. Platelet count represents a readily-available laboratory value that may preoperatively improve risk-stratification of patients undergoing curative-intent liver resection for ICC.

Early Recurrence After Resection of Locally Advanced Pancreatic Cancer Following Induction Therapy: An International Multicenter Study.

OBJECTIVE: To establish an evidence-based cutoff and predictors for early recurrence in patients with resected locally advanced pancreatic cancer (LAPC). BACKGROUND: It is unclear how many and which patients develop early recurrence after LAPC resection. Surgery in these patients is probably of little benefit. METHODS: We analyzed all consecutive patients undergoing resection of LAPC after induction chemotherapy who were included in prospective databases in The Netherlands (2015-2019) and the Johns Hopkins Hospital (2016-2018). The optimal definition for "early recurrence" was determined by the post-recurrence survival (PRS). Patients were compared for overall survival (OS). Predictors for early recurrence were evaluated using logistic regression analysis. RESULTS: Overall, 168 patients were included. After a median follow-up of 28 months, recurrence was observed in 118 patients (70.2%). The optimal cutoff for recurrence-free survival to differentiate between early (n=52) and late recurrence (n=66) was 6 months ( P <0.001). OS was 8.4 months [95% confidence interval (CI): 7.3-9.6] in the early recurrence group (n=52) versus 31.1 months (95% CI: 25.7-36.4) in the late/no recurrence group (n=116) ( P <0.001). A preoperative predictor for early recurrence was postinduction therapy carbohydrate antigen (CA) 19-9≥100 U/mL [odds ratio (OR)=4.15, 95% CI: 1.75-9.84, P =0.001]. Postoperative predictors were poor tumor differentiation (OR=4.67, 95% CI: 1.83-11.90, P =0.001) and no adjuvant chemotherapy (OR=6.04, 95% CI: 2.43-16.55, P <0.001). CONCLUSIONS: Early recurrence was observed in one third of patients after LAPC resection and was associated with poor survival. Patients with post-induction therapy CA 19-9 ≥100 U/mL, poor tumor differentiation and no adjuvant therapy were especially at risk. This information is valuable for patient counseling before and after resection of LAPC.

Short-term Outcomes After Spleen-preserving Minimally Invasive Distal Pancreatectomy With or Without Preservation of Splenic Vessels: A Pan-European Retrospective Study in High-volume Centers.

OBJECTIVE: To compare short-term clinical outcomes after Kimura and Warshaw MIDP. BACKGROUND: Spleen preservation during distal pancreatectomy can be achieved by either preservation (Kimura) or resection (Warshaw) of the splenic vessels. Multicenter studies reporting outcomes of Kimura and Warshaw spleen-preserving MIDP are scarce. METHODS: Multicenter retrospective study including consecutive MIDP procedures intended to be spleen-preserving from 29 high-volume centers (≥15 distal pancreatectomies annually) in 8 European countries. Primary outcomes were secondary splenectomy for ischemia and major (Clavien-Dindo grade ≥III) complications. Sensitivity analysis assessed the impact of excluding ("rescue") Warshaw procedures which were performed in centers that typically (>75%) performed Kimura MIDP. RESULTS: Overall, 1095 patients after MIDP were included with successful splenic preservation in 878 patients (80%), including 634 Kimura and 244 Warshaw procedures. Rates of clinically relevant splenic ischemia (0.6% vs 1.6%, P = 0.127) and major complications (11.5% vs 14.4%, P = 0.308) did not differ significantly between Kimura and Warshaw MIDP, respectively. Mortality rates were higher after Warshaw MIDP (0.0% vs 1.2%, P = 0.023), and decreased in the sensitivity analysis (0.0% vs 0.6%, P = 0.052). Kimura MIDP was associated with longer operative time (202 vs 184 minutes, P = 0.033) and less blood loss (100 vs 150 mL, P < 0.001) as compared to Warshaw MIDP. Unplanned splenectomy was associated with a higher conversion rate (20.7% vs 5.0%, P < 0.001). CONCLUSIONS: Kimura and Warshaw spleen-preserving MIDP provide equivalent short-term outcomes with low rates of secondary splenectomy and postoperative morbidity. Further analyses of long-term outcomes are needed.

Robotic Distal Pancreatectomy: A Novel Standard of Care? Benchmark Values for Surgical Outcomes From 16 International Expert Centers.

BACKGROUND AND OBJECTIVE: Robotic distal pancreatectomy (DP) is an emerging attractive approach, but its role compared with laparoscopic or open surgery remains unclear. Benchmark values are novel and objective tools for such comparisons. The aim of this study was to identify benchmark cutoffs for many outcome parameters for DP with or without splenectomy beyond the learning curve. METHODS: This study analyzed outcomes from international expert centers from patients undergoing robotic DP for malignant or benign lesions. After excluding the first 10 cases in each center to reduce the effect of the learning curve, consecutive patients were included from the start of robotic DP up to June 2020. Benchmark patients had no significant comorbidities. Benchmark cutoff values were derived from the 75th or the 25th percentile of the median values of all benchmark centers. Benchmark values were compared with a laparoscopic control group from 4 high-volume centers and published open DP landmark series. RESULTS: Sixteen centers contributed 755 cases, whereof 345 benchmark patients (46%) were included the analysis. Benchmark cutoffs included: operation time ≤300 minutes, conversion rate ≤3%, clinically relevant postoperative pancreatic fistula ≤32%, 3 months major complication rate ≤26.7%, and lymph node retrieval ≥9. The comprehensive complication index at 3 months was ≤8.7 without deterioration thereafter. Compared with robotic DP, laparoscopy had significantly higher conversion rates (5×) and overall complications, while open DP was associated with more blood loss and longer hospital stay. CONCLUSION: This first benchmark study demonstrates that robotic DP provides superior postoperative outcomes compared with laparoscopic and open DP. Robotic DP may be expected to become the approach of choice in minimally invasive DP.

Current Practices in Hepatic Artery Infusion (HAI) Chemotherapy: An International Survey of the HAI Consortium Research Network.

BACKGROUND: An increasing number of hepatic artery infusion (HAI) programs have been established worldwide. Practice patterns for this complex therapy across these programs have not been reported. This survey aimed to identify current practice patterns in HAI therapy with the long-term goal of defining best practices and performing prospective studies. METHODS: Using SurveyMonkeyTM, a 28-question survey assessing current practices in HAI was developed by 12 HAI Consortium Research Network (HCRN) surgical oncologists. Content analysis was used to code textual responses, and the frequency of categories was calculated. Scores for rank-order questions were generated by calculating average ranking for each answer choice. RESULTS: Thirty-six (72%) HCRN members responded to the survey. The most common intended initial indications for HAI at new programs were unresectable colorectal liver metastases (uCRLM; 100%) and unresectable intrahepatic cholangiocarcinoma (uIHC; 56%). Practice patterns evolved such that uCRLM (94%) and adjuvant therapy for CRLM (adjCRLM; 72%) have become the most common current indications for HAI at established centers. Referral patterns for pump placement differed between uCRLM and uIHC, with most patients referred while receiving second- and first-line therapy, respectively, with physicians preferring to evaluate patients for HAI while receiving first-line therapy for CRLM. Concern for extrahepatic disease was ranked as the most important factor when considering a patient for HAI. CONCLUSIONS: Indication and patient selection factors for HAI therapy are relatively uniform across most HCRN centers. The increasing use of adjuvant HAI therapy and overall consistency of practice patterns among HCRN centers provides a robust environment for prospective data collection and randomized clinical trials.

Development and Validation of a Machine-Learning Model to Predict Early Recurrence of Intrahepatic Cholangiocarcinoma.

BACKGROUND: The high incidence of early recurrence after hepatectomy for intrahepatic cholangiocarcinoma (ICC) has a detrimental effect on overall survival (OS). Machine-learning models may improve the accuracy of outcome prediction for malignancies. METHODS: Patients who underwent curative-intent hepatectomy for ICC were identified using an international database. Three machine-learning models were trained to predict early recurrence (< 12 months after hepatectomy) using 14 clinicopathologic characteristics. The area under the receiver operating curve (AUC) was used to assess their discrimination ability. RESULTS: In this study, 536 patients were randomly assigned to training (n = 376, 70.1%) and testing (n = 160, 29.9%) cohorts. Overall, 270 (50.4%) patients experienced early recurrence (training: n = 150 [50.3%] vs testing: n = 81 [50.6%]), with a median tumor burden score (TBS) of 5.6 (training: 5.8 [interquartile range {IQR}, 4.1-8.1] vs testing: 5.5 [IQR, 3.7-7.9]) and metastatic/undetermined nodes (N1/NX) in the majority of the patients (training: n = 282 [75.0%] vs testing n = 118 [73.8%]). Among the three different machine-learning algorithms, random forest (RF) demonstrated the highest discrimination in the training/testing cohorts (RF [AUC, 0.904/0.779] vs support vector machine [AUC, 0.671/0.746] vs logistic regression [AUC, 0.668/0.745]). The five most influential variables in the final model were TBS, perineural invasion, microvascular invasion, CA 19-9 lower than 200 U/mL, and N1/NX disease. The RF model successfully stratified OS relative to the risk of early recurrence. CONCLUSIONS: Machine-learning prediction of early recurrence after ICC resection may inform tailored counseling, treatment, and recommendations. An easy-to-use calculator based on the RF model was developed and made available online.